If the above-mentioned nuts and screws are used as a kind of fasteners that can prevent others from being disassembled, such as when installing iron doors-steel windows, people usually tighten the nuts first, and then use a welding machine to weld the nuts and screws. To prevent the nut from loosening, it may be necessary to use a tool to mill the threads on the screw. It can be seen that this approach is very inconvenient.
Rivet nuts, pull caps, and instant pull caps are widely used in the assembly of electromechanical and light industrial products such as automobiles, aviation, instruments, furniture, and decoration. It is developed to solve the shortcomings of thin metal plate and thin tube welding nuts, such as easy melting and easy sliding of internal threads. Chinese name rivet nut, foreign name Rivetnut, blinddrivetnut, threadedforbid, rivnut, also known as rivet nut, is used in various metal sheets, pipes and other manufacturing industrial applications in railways, refrigeration, elevators, switches
When using screws, if you can understand the mechanical properties of screws first, then you can use screws better. Different types of screws have different mechanical properties, and the different mechanical properties lead to different occasions when screws are used. 1. Self-tapping screws: mechanical performance requirements 1. Heart hardness: standard value HRC28-38. When testing, take the section 1-2 times the diameter of the name from the tail. If the length of the name is too short, it can be embedded first, and then the hardness is measured. 2. Surface hardness: standard MIN HV450. 3. Carburized layer: standard 4#-6#: 0.05-0.18mm, 8#-12#: 0.10-0.23 mm, 14#: 0.13-0.28 mm. The main purpose of carburizing is to enhance the surface hardness and ensure the strength of the teeth. If the decarburization is too deep and the carburization is insufficient, the strength of the teeth will not meet the requirements, that is, the teeth will be damaged during the screw-in test. 4. Torque: standard specification 4#5#6#7#8#10#12#14#A tooth 14212835455696145AB tooth 142128354565102165. 5. Screw-in test: screw the self-tapping screw into a steel plate with a reserved test hole. The self-tapping screw should form a matching thread in the test plate, and the thread of the screw itself will not be deformed or damaged until the end. Tapered threads pass completely through the test plate. The screw-in test is only applicable to AB, B, BP and other types of self-tapping screws. It is stipulated in IFI that the test plate shall be prepared from semi-hard low-carbon cold-rolled steel, and the hardness of the steel plate is 70–85HRB in Rockwell. The standard specification of the steel plate, that is, the thickness, is shown in the table below. The test hole should be punched or drilled, and the tolerance is the specified nominal diameter (see the table below) ± 0.025mm. Specifications 6#7#8#10#12#1/4 Test plate thickness (mm) 1.85-1.953.12-3.234.68-4.84 Aperture (mm) ±0.0252.953.263.454.044.765.50.
Many customers ask what is the difference between a rivet nut and a rivet nut, and how to use it? Let's take a look at the difference between a rivet nut and a rivet nut with Yueluo. First of all, in terms of appearance, you can look at the differences in appearance. In terms of appearance, the difference between the rivet nut and the pressure rivet nut is still very big, but their main functions are almost the same. They all provide threads for thin plates, but the way of installation is different. The method of installation greatly determines the purpose and use of a nut. First of all, the installation method of the riveting nut is to use the riveting equipment to carry out the riveting, so it is suitable for use in the place where the riveting is not easy for the square tube and the round tube. The rivet nut also makes up for some of the shortcomings of electric welding, such as aesthetics, and places that are not easy to weld, such as thin plates.
The national standard for the size of the screws in the round head three-combination screw is GB818. The main technical requirements of various types are: iron and stainless steel for material requirements, low, medium and high carbon steel for iron, and stainless steel combination screws The materials are stainless steel 201, stainless steel 304 and stainless steel 316. The thread tolerance is 6G, and the mechanical properties of the iron combination screws are 4.8 and 8.8. The 4.8-level combination screws are ordinary steel, and the maximum allowable hardness is 255HV. The 8.8-level combination screws are generally made of wire rod 10B21. , and then undergo hardening treatment, and then dehydrogenation after hardening treatment. Hydrogen removal is to prevent hydrogen embrittlement of the spring washer in the combination screw. Prevent the spring pad from breaking. The tolerance class of the combination screws is A. The cross groove is H-shaped. The surface treatment of the combination screw has environmental protection and non-environmental protection. Such as, environmental protection blue zinc, environmental protection color zinc, black zinc, color zinc, white nickel and so on. The technical requirement of the combination screw for the spring washer is that the washer should be able to rotate automatically without falling off.
We have many years of experience in the production and sales of screws, nuts, flat washers, etc. The main products are: hexagon nuts, hand-tightening adjustment screws and nuts, extended hexagon head bolts, anti-theft screws and other products, we can provide you with suitable fasteners for you solution.